The HSZG in the Swiss Alps
The Faculty of Electrical Engineering and Computer Science' visits the "Grimsel 2" power plant.
From September 6–8, the HSZG visited Kraftwerke Oberhasli AG (KWO), represented by Prof. Uwe Schmidt and Jonathan Hänsch from the EI faculty. The purpose of the trip was to visit the Grimsel 2 pumped-storage power plant, where various measurements were conducted in its modern 245-kV switchgear. The goal of the measurements was to investigate transient processes that occur when the turbines are brought online.
The Grimsel 2 power plant has four turbine groups with a total capacity of 344 MW in generator mode and 363 MW in pump mode. It was built between 1973 and 1980 and is located in southern Switzerland.
Pumped-storage power plants are fundamentally important components of the power grid because they are capable of storing large amounts of energy. In addition, they can respond to changing demands on the transmission grids within minutes. Due to their characteristics, they contribute to the stabilization of the European power grid. The Alpine region offers ideal conditions for hydroelectric power plants and pumped-storage power plants.
The power plant’s 245-kV switchgear is designed as a gas-insulated switchgear (GIS) system. The highly compact design of a gas-insulated switchgear system is a decisive advantage for use in a cavern power plant. A pressurized gas, usually SF6, is used as the insulating medium. The switchgear connects the individual units of the power plant to the transmission grid of Swissgrid AG, the Swiss transmission system operator.